WASHINGTON — The report detailing the supposed vulnerability of the Army's Stryker armored vehicles to rocket-propelled grenades appeared on a password-protected terrorist Web site in the summer of 2006.
Terrorists discovered it on the Web site of a think tank, downloaded it to their own site and urged fellow mujahedeen to study it and use what they learned in attacking the U.S. combat vehicles in Iraq.
Though the report has been discredited, its posting on a jihadist Web site shows how cyberspace has become an increasingly important front in the war on terror.
From "Jihad University" to "Terrorists 007" to 5,000 or more other sites, terrorists are using the Internet to spread propaganda, recruit members, raise money, offer training and instruction and plan operations.
The National Security Agency, the CIA, the FBI, the Defense Intelligence Agency, other U.S. and foreign intelligence agencies and some private contractors are fighting back, cracking terrorist passwords, monitoring suspicious Web sites, cyberattacking others and sometimes planting bogus information.
Some lawmakers on Capitol Hill and independent experts, however, think the U.S. could be doing a better job to counter the threat.
"It's not like we aren't looking at these sites," said Rep. Adam Smith, D-Wash., the chairman of the House Armed Services terrorism subcommittee. "But we need better coordination, processing of what we find. It's a major concern."
"The government efforts are inadequate," said Bruce Hoffman, a professor in the Securities Studies Program at Georgetown University, who suggested that the private sector is doing a better job than the government is. "Our enemies have embraced the Internet. We have to ask how closely the government is monitoring it."
Much of what the intelligence community is doing is classified, and few details are available.
"People look at this issue on a regular basis and are aware of its importance," said one senior U.S. intelligence official who spoke only on the condition that he wouldn't be identified. "There is significant interagency cooperation."
At the Department of Homeland Security, the focus has been on protecting government and private Web sites from cyberattacks by terrorists and other hackers who want to pilfer classified information or crash the sites with waves of e-mail.
"There are intrusions happening everyday," said Russ Knocke, a Homeland Security spokesman. "There is no evidence of activity tied to the terror network. But it remains something we are concerned about."
Congressman Smith said the U.S. government has launched an effort to counter some of the propaganda that terrorists post in Internet chat rooms, message boards, blogs and other Web sites. He said the government programs use some "fairly cool stuff" that he can't talk about publicly.
The Internet threat is wide-ranging, complicated and not easy to contain.
Some sites include veritable libraries of videos showing attacks on U.S. forces in Iraq. Elsewhere, there are realistic video games based on attacking U.S. forces in Iraq or Israelis featuring figures such as "Juba, the sniper." Sites that show videos of beheadings have been known to crash because so many people are trying to get online.
"They are enormously useful for providing motivation," said Daniel Benjamin, a senior fellow at the Brookings Institution, a center-left policy organization in Washington and a former director of counterterrorism for the National Security Council in the Clinton White House.
Terrorist sites can contain instructions on how to use small arms, mortars and rockets, build bombs and train to become a sniper. Some analysts say the training and instruction offered on the Internet have largely replaced the terrorist training camps that al Qaida established in Afghanistan and elsewhere in the 1980s and 1990s.
The sites also can contain clues of what terrorists may be planning, Benjamin said, adding that a document, written in Arabic and found by Norwegian intelligence analysts, suggested that Spain was the weakest link in the U.S.-led Iraq coalition and that violent action could undermine Spanish support for the war. The document supposedly was posted online before the bombing attacks in Madrid several years ago.
Terrorists share tactics, techniques and procedures using off-the-shelf encryption, and some embed messages or operational instructions in seemingly harmless pictures or audio files in a high-tech game of cat-and-mouse known as steganography.
"It's network-centric warfare, and we gave them the tools," said Loren Thompson of the Lexington Institute, a public policy research group that focuses on military issues. "There is no limit to how they can use the Internet. A terrorist can walk into an Internet cafe in Islamabad and within a minute communicate with 10,000 people."
Countering the threat isn't easy and could, in fact, be counterproductive.
"The knee-jerk reaction is always to shut them (terrorist Web sites) down," Benjamin said. "It is easily feasible, and it may not be in our best interests."
Benjamin and others believe that by closely monitoring the Web sites, intelligence officials are collecting valuable information on what terrorists are thinking and planning. Shutting down the sites could interfere with that effort.
In addition, if a site is taken down, it probably will pop up somewhere else, he said.